InlineCssModule

using System;
using System.IO;
using System.Web;

/// <summary>
/// Removes CSS from rendered HTML page.
/// </summary>
public class InlineCssModule : IHttpModule
{

	#region IHttpModule Members

	void IHttpModule.Dispose()
	{
		// Nothing to dispose; 
	}

	void IHttpModule.Init(HttpApplication context)
	{
		context.BeginRequest += new EventHandler(context_BeginRequest);
	}

	#endregion

	static void context_BeginRequest(object sender, EventArgs e)
	{
		HttpApplication app = sender as HttpApplication;
		if (app.Request.AppRelativeCurrentExecutionFilePath.StartsWith("~/media/email/"))
		{
			app.Response.Filter = new InlineCssFilter(app.Response.Filter);
		}
	}

	#region Stream filter

	private class InlineCssFilter : Stream
	{
		private static global::PreMailer.Net.PreMailer pm = new global::PreMailer.Net.PreMailer();
		public InlineCssFilter(Stream sink)
		{
			_sink = sink;
		}

		private readonly Stream _sink;

		#region Properites

		public override bool CanRead
		{
			get { return true; }
		}

		public override bool CanSeek
		{
			get { return true; }
		}

		public override bool CanWrite
		{
			get { return true; }
		}

		public override void Flush()
		{
			_sink.Flush();
		}

		public override long Length
		{
			get { return 0; }
		}

		public override long Position { get; set; }

		#endregion

		#region Methods

		public override int Read(byte[] buffer, int offset, int count)
		{
			return _sink.Read(buffer, offset, count);
		}

		public override long Seek(long offset, SeekOrigin origin)
		{
			return _sink.Seek(offset, origin);
		}

		public override void SetLength(long value)
		{
			_sink.SetLength(value);
		}

		public override void Close()
		{
			_sink.Close();
		}

		public override void Write(byte[] buffer, int offset, int count)
		{
			byte[] data = new byte[count];
			Buffer.BlockCopy(buffer, offset, data, 0, count);
			string html = System.Text.Encoding.Default.GetString(buffer);

			html = pm.MoveCssInline(html, true);

			byte[] outdata = System.Text.Encoding.Default.GetBytes(html);
			_sink.Write(outdata, 0, outdata.GetLength(0));
		}

		#endregion

	}

	#endregion

}